Revert "[cleanup] Remove dead code"

This reverts commit 26bc275ce1.

Reason for revert: used in devtools-internal so breaks the roll

Original change's description:
> [cleanup] Remove dead code
>
> The infra now all uses `npm run lint` for linting.
> Moves a common function to the only place it's used.
>
> Bug: none
> Change-Id: Ibcf86daa95e33d8b313efe76a6173436769786d5
> Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/6070376
> Commit-Queue: Nikolay Vitkov <nvitkov@chromium.org>
> Auto-Submit: Nikolay Vitkov <nvitkov@chromium.org>
> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>

Bug: none
Change-Id: I090c1750ec1ada53df22c443253922162f41e271
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/6072803
Reviewed-by: Simon Zünd <szuend@chromium.org>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Commit-Queue: Alex Rudenko <alexrudenko@chromium.org>

scripts/component_server/BUILD.gn

@@ -7,5 +7,8 @@ import("../build/ninja/copy.gni")
 copy_to_gen("component_server") {
   sources = [ "server.js" ]
 
-  deps = [ "../../front_end/ui/legacy:copy_stylesheets_for_server" ]
+  deps = [
+    "../../front_end/ui/legacy:copy_stylesheets_for_server",
+    "../test",
+  ]
 }

scripts/component_server/server.js

@@ -8,22 +8,11 @@ const path = require('path');
 const parseURL = require('url').parse;
 const {argv} = require('yargs');
 
+const {getTestRunnerConfigSetting} = require('../test/test_config_helpers.js');
+
 const tracesMode = argv.traces || false;
 const serverPort = parseInt(process.env.PORT, 10) || (tracesMode ? 11010 : 8090);
 
-function getTestRunnerConfig() {
-  try {
-    return JSON.parse(process.env.TEST_RUNNER_JSON_CONFIG);
-  } catch {
-    // Return an empty object so any lookups return undefined
-    return {};
-  }
-}
-function getTestRunnerConfigSetting(settingKey, fallbackValue) {
-  const config = getTestRunnerConfig();
-  return config[settingKey] === undefined ? fallbackValue : config[settingKey];
-}
-
 /**
  * When you run npm run components-server we run the script as is from scripts/,
  * but when this server is run as part of a test suite it's run from

scripts/test/BUILD.gn

@@ -0,0 +1,9 @@
+# Copyright 2021 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("../build/ninja/copy.gni")
+
+copy_to_gen("test") {
+  sources = [ "test_config_helpers.js" ]
+}

scripts/test/run_lint_check.py

@@ -0,0 +1,35 @@
+#!/usr/bin/env vpython3
+#
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# TODO(1083142): remove this file in favor of run_lint_check_js.py once
+# infra has been updated.
+
+import sys
+from os import path
+from subprocess import Popen
+
+scripts_path = path.dirname(path.dirname(path.abspath(__file__)))
+sys.path.append(scripts_path)
+import devtools_paths
+
+CURRENT_DIRECTORY = path.dirname(path.abspath(__file__))
+ROOT_DIRECTORY = path.normpath(path.join(CURRENT_DIRECTORY, '..', '..'))
+
+
+def main():
+    exec_command = [
+        devtools_paths.node_path(),
+        path.join(CURRENT_DIRECTORY, 'run_lint_check_js.mjs'),
+    ]
+
+    eslint_proc = Popen(exec_command, cwd=ROOT_DIRECTORY)
+    eslint_proc.communicate()
+
+    sys.exit(eslint_proc.returncode)
+
+
+if __name__ == '__main__':
+    main()

scripts/test/run_lint_check_css.js

@@ -0,0 +1,62 @@
+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+const path = require('path');
+const childProcess = require('child_process');
+const {
+  devtoolsRootPath,
+  stylelintExecutablePath,
+  nodePath,
+} = require('../devtools_paths.js');
+
+const yargsObject = require('yargs')
+                        .option('files', {type: 'array', desc: 'One or more files to lint.'})
+                        .option('glob', {default: '**/*.css', desc: 'A glob to choose which files to lint.'})
+                        .option('cwd', {default: devtoolsRootPath(), desc: 'Working directory to glob from'})
+                        .parserConfiguration({
+                          // So that if we pass --foo-bar, Yargs only populates
+                          // argv with '--foo-bar', not '--foo-bar' and
+                          // 'fooBar'. This is important because if we have both
+                          // versions and pass them to stylelint, it errors
+                          // saying that we've passed the same argument twice.
+                          'camel-case-expansion': false
+                        })
+                        .argv;
+
+// Note: stylelint requires POSIX-formatted paths/globs, even on Windows.
+// The forward slash is not a bug.
+const DEFAULT_GLOB = '**/*.css';
+
+function getCSSFilesOrGlobList() {
+  const files = yargsObject.files || [];
+  if (files.length > 0) {
+    return files.map(file => {
+      // Enforce posix file paths even on Windows
+      return file.split(path.sep).join(path.posix.sep);
+    });
+  }
+
+  return [yargsObject.glob || DEFAULT_GLOB];
+}
+
+function run() {
+  // eslint-disable-next-line no-unused-vars
+  const {glob, files, cwd, _, $0, ...flagsForStylelint} = yargsObject;
+
+  const extraFlagsForStylelint = Object.keys(flagsForStylelint).flatMap(key => [`--${key}`, flagsForStylelint[key]]);
+
+  const args = [
+    stylelintExecutablePath(), ...getCSSFilesOrGlobList(), '--fix', '--allow-empty-input', ...extraFlagsForStylelint
+  ];
+  const result = childProcess.spawnSync(nodePath(), args, {encoding: 'utf-8', cwd, stdio: 'inherit'});
+  if (result.error) {
+    // If spawnSync returns an error, exit with an error no matter what result.status says.
+    console.error(result.error);
+    process.exit(1);
+    return;
+  }
+  process.exit(result.status);
+}
+
+run();

scripts/test/run_lint_check_js.mjs

@@ -0,0 +1,81 @@
+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Use V8's code cache to speed up instantiation time.
+await import('v8-compile-cache');
+
+import path from 'path';
+import {ESLint} from 'eslint';
+import { fileURLToPath } from 'url';
+
+import yargs from 'yargs';
+
+// False positive from the ESLint rule: crbug.com/1319352
+// eslint-disable-next-line rulesdir/es_modules_import
+import {hideBin} from 'yargs/helpers';
+
+const flags = yargs(hideBin(process.argv)).option('fix', {
+  type: 'boolean',
+  default: true,
+  describe: 'If to run ESLint in fix mode',
+}).parse();
+
+const shouldFix = flags.fix === true;
+
+if(!shouldFix) {
+  console.log('[ESLint]: fix is disabled; no errors will be autofixed.');
+}
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+
+const ROOT_DIRECTORY = path.join(__dirname, '..', '..');
+const FRONT_END_DIRECTORY = path.join(ROOT_DIRECTORY, 'front_end');
+const INSPECTOR_OVERLAY_DIRECTORY = path.join(ROOT_DIRECTORY, 'inspector_overlay');
+const TEST_DIRECTORY = path.join(ROOT_DIRECTORY, 'test');
+const SCRIPTS_DIRECTORY = path.join(ROOT_DIRECTORY, 'scripts');
+
+const DEFAULT_DIRECTORIES_TO_LINT =
+    [FRONT_END_DIRECTORY, INSPECTOR_OVERLAY_DIRECTORY, TEST_DIRECTORY, SCRIPTS_DIRECTORY];
+
+const eslintignorePath = path.join(ROOT_DIRECTORY, '.eslintignore');
+
+// Yargs gathers up any non-flag arguments into the `_` property.
+// npm run check-lint-js foo => flags._ === ['foo']
+let directoriesOrFilesToLint = flags._;
+
+if (directoriesOrFilesToLint.length === 0) {
+  directoriesOrFilesToLint = DEFAULT_DIRECTORIES_TO_LINT;
+}
+
+const cli = new ESLint({
+  extensions: ['.js', '.ts'],
+  ignorePath: eslintignorePath,
+  fix: shouldFix,
+});
+
+// We filter out certain files in the `.eslintignore`. However, ESLint produces warnings
+// when you include a particular file that is ignored. This means that if you edit a file
+// that is directly ignored in the `.eslintignore`, ESLint would report a failure.
+// This was originally reported in https://github.com/eslint/eslint/issues/9977
+// The suggested workaround is to use the CLIEngine to pre-emptively filter out these
+// problematic paths.
+const filteredFilesToLint = [];
+for (const path of directoriesOrFilesToLint) {
+  if (!(await cli.isPathIgnored(path))) {
+    filteredFilesToLint.push(path);
+  }
+}
+
+const results = await cli.lintFiles(filteredFilesToLint);
+
+// Write fixes to the filesystem
+if (shouldFix) {
+  await ESLint.outputFixes(results);
+}
+
+const formatter = await cli.loadFormatter('stylish');
+console.log(formatter.format(results));
+
+const hasProblems = results.find(report => report.errorCount + report.warningCount > 0);
+process.exit(hasProblems ? 1 : 0);

scripts/test/run_lint_check_js.py

@@ -0,0 +1,32 @@
+#!/usr/bin/env vpython3
+#
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import sys
+from os import path
+from subprocess import Popen
+
+scripts_path = path.dirname(path.dirname(path.abspath(__file__)))
+sys.path.append(scripts_path)
+import devtools_paths
+
+CURRENT_DIRECTORY = path.dirname(path.abspath(__file__))
+ROOT_DIRECTORY = path.normpath(path.join(CURRENT_DIRECTORY, '..', '..'))
+
+
+def main():
+    exec_command = [
+        devtools_paths.node_path(),
+        path.join(CURRENT_DIRECTORY, 'run_lint_check_js.mjs'),
+    ]
+
+    eslint_proc = Popen(exec_command, cwd=ROOT_DIRECTORY)
+    eslint_proc.communicate()
+
+    sys.exit(eslint_proc.returncode)
+
+
+if __name__ == '__main__':
+    main()

scripts/test/test_config_helpers.js

@@ -0,0 +1,29 @@
+// Copyright 2021 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+function getTestRunnerConfig() {
+  try {
+    return JSON.parse(process.env.TEST_RUNNER_JSON_CONFIG);
+  } catch {
+    // Return an empty object so any lookups return undefined
+    return {};
+  }
+}
+function getTestRunnerConfigSetting(settingKey, fallbackValue) {
+  const config = getTestRunnerConfig();
+  return config[settingKey] === undefined ? fallbackValue : config[settingKey];
+}
+function requireTestRunnerConfigSetting(settingKey, errorMessage) {
+  const config = getTestRunnerConfig();
+  if (config[settingKey] === undefined) {
+    throw new Error(errorMessage || `Test runner error: could not find required setting ${settingKey}`);
+  }
+
+  return config[settingKey];
+}
+
+module.exports = {
+  getTestRunnerConfigSetting,
+  requireTestRunnerConfigSetting
+};